Browsing Pathways

The process of flavin biosynthesis starts with GTP being metabolized by interacting with 3 molecules of water through a GTP cyclohydrolase resulting in a release of formic acid, a pyrophosphate, two hydrog ions and 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one or 2,5-Diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine. Either of these compounds interacts with a water molecule and a hydrogen ion through a fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in an ammonium and 5-amino-6-(5-phospho-D-ribosylamino)uracil. This compound then interacts with a hydrogen ion through a NADPH dependent fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in the release of a NADP and a 5-amino-6-(5-phospho-D-ribitylamino)uracil. This compound then interacts with a water molecule through a 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase resulting in a release of a phosphate, and a 5-amino-6-(D-ribitylamino)uracil. D-ribulose 5-phosphate interacts with a3,4-dihydroxy-2-butanone 4-phosphate synthase resulting in the release of formic acid, a hydrogen ion and 1-deoxy-L-glycero-tetrulose 4-phosphate. A 5-amino-6-(D-ribitylamino)uracil and 1-deoxy-L-glycero-tetrulose 4-phosphate interact through a 6,7-dimethyl-8-ribityllumazine synthase resulting in the release of 2 water molecules, a phosphate, a hydrogen ion and a 6,7-dimethyl-8-(1-D-ribityl)lumazine. The latter compound then interacts with a hydrogen ion through a riboflavin synthase resulting in the release of a riboflavin and a 5-amino-6-(d-ribitylamino)uracil. The riboflavin is then phosphorylated through an ATP dependent riboflavin kinase resulting in the release of a ADP, a hydrogen ion and a FLAVIN MONONUCLEOTIDE. The flavin mononucleotide interad with a hydrogen ion and an ATP through the riboflavin kinase resulting in the release of a pyrophosphate and Flavin Adenine dinucleotide. This compound is then exported into the periplasm through a FMN/FAD exporter.

The process of flavin biosynthesis starts with GTP being metabolized by interacting with 3 molecules of water through a GTP cyclohydrolase resulting in a release of formic acid, a pyrophosphate, two hydrog ions and 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one or 2,5-Diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine. Either of these compounds interacts with a water molecule and a hydrogen ion through a fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in an ammonium and 5-amino-6-(5-phospho-D-ribosylamino)uracil. This compound then interacts with a hydrogen ion through a NADPH dependent fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in the release of a NADP and a 5-amino-6-(5-phospho-D-ribitylamino)uracil. This compound then interacts with a water molecule through a 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase resulting in a release of a phosphate, and a 5-amino-6-(D-ribitylamino)uracil. D-ribulose 5-phosphate interacts with a3,4-dihydroxy-2-butanone 4-phosphate synthase resulting in the release of formic acid, a hydrogen ion and 1-deoxy-L-glycero-tetrulose 4-phosphate. A 5-amino-6-(D-ribitylamino)uracil and 1-deoxy-L-glycero-tetrulose 4-phosphate interact through a 6,7-dimethyl-8-ribityllumazine synthase resulting in the release of 2 water molecules, a phosphate, a hydrogen ion and a 6,7-dimethyl-8-(1-D-ribityl)lumazine. The latter compound then interacts with a hydrogen ion through a riboflavin synthase resulting in the release of a riboflavin and a 5-amino-6-(d-ribitylamino)uracil. The riboflavin is then phosphorylated through an ATP dependent riboflavin kinase resulting in the release of a ADP, a hydrogen ion and a FLAVIN MONONUCLEOTIDE. The flavin mononucleotide interad with a hydrogen ion and an ATP through the riboflavin kinase resulting in the release of a pyrophosphate and Flavin Adenine dinucleotide. This compound is then exported into the periplasm through a FMN/FAD exporter.

The biosynthesis of Valine and L-leucine from pyruvic acid starts with pyruvic acid interacting with a hydrogen ion through a acetolactate synthase / acetohydroxybutanoate synthase resulting in a release of a carbon dioxide, a (S)-2-acetolactate. The latter compound then interacts with a hydrogen ion through a NADPH-driven acetohydroxy acid isomeroreductase resulting in the release of a NADP, a (R) 2,3-dihydroxy-3-methylvalerate. The latter compound is then dehydrated by a dihydroxy acid dehydratase resulting in the release of a water molecule an 3-methyl-2-oxovaleric acid. The 3-methyl-2-oxovaleric acid can produce an L-valine by interacting with a L-glutamic acid through a Valine Transaminase resulting in the release of a Oxoglutaric acid and a L-valine. The 3-methyl-2-oxovaleric acid then interacts with an acetyl-CoA and a water molecule through a 2-isopropylmalate synthase resulting in the release of a hydrogen ion, a Coenzyme A and a 2-Isopropylmalic acid. The isopropylimalic acid is then hydrated by interacting with a isopropylmalate isomerase resulting in a 3-isopropylmalate. This compound then interacts with an NAD driven 3-isopropylmalate dehydrogenase resulting in a NADH, a hydrogen ion and a 2-isopropyl-3-oxosuccinate. The latter compound then interacts with hydrogen ion spontaneously resulting in a carbon dioxide and a ketoleucine. The ketoleucine then interacts with a L-glutamic acid through a branched-chain amino-acid aminotransferase resulting in the oxoglutaric acid and L-leucine.

Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor.

Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor.

The process of oleic acid B-oxidation starts with a 2-trans,5-cis-tetradecadienoyl-CoA that can be either be processed by an enoyl-CoA hydratase by interacting with a water molecules resulting in a 3-hydroxy-5-cis-tetradecenoyl-CoA, which can be oxidized in the fatty acid beta-oxidation. On the other hand 2-trans,5-cis-tetradecadienoyl-CoA can become a 3-trans,5-cis-tetradecadienoyl-CoA through a isomerase. This results interact with a water molecule through a acyl-CoA thioesterase resulting in a hydrogen ion, a coenzyme A and a 3,5-tetradecadienoate

Pseudouridine is phosphorylated by interacting with atp and a psuK resulting in the release of an ADP, a hydrogen ion and a pseudouridine 5'-phosphate. The latter compound then reacts with water through a pseudouridine 5'-phosphate glycosidase resulting in the release of a uracil and D-ribofuranose 5-phosphate

Pseudouridine is phosphorylated by interacting with atp and a psuK resulting in the release of an ADP, a hydrogen ion and a pseudouridine 5'-phosphate. The latter compound then reacts with water through a pseudouridine 5'-phosphate glycosidase resulting in the release of a uracil and D-ribofuranose 5-phosphate

The ketogluconate metabolism starts with the degradation of 2,5-didehydro-D-gluconate either through a NADPH dependent 2,5-diketo-D-gluconate reductase resulting in the release of a NADP and 5-dehydro-D-gluconate or through a NADPH dependent 2,5-diketo-D-gluconate reductase protein complex resulting in the release of a NADP and a 2-keto-L-gulonate. The 2-keto-L-gulonate interacts with a NADPH 2-keto-L-gulonate reductase resulting in a NADP and a L-idonate. The L-idonate interacts with a NADP L-idonate 5-dehydrogenase resulting in the release of hydrogen ion, a NADPH and a 5-dehydro-D-gluconate. The 5-dehydro-D-gluconate interacts with a NADPH driven 5-keto-D-gluconate 5-reductase resulting in the release of a NADP and a D-gluconate. The other way to produce D-gluconate is by having 2,5-Didehydro-D-gluconate interacting with a NADPH and hydrogen ion resulting in the release of a NADP and a 2-keto-D-gluconate which then interact with NADPH a 2-keto-D-gluconate reductase resulting in a NADP and a D-gluconate The D-gluconate is phosphorylated by an ATP driven D-gluconate kinase resulting in a ADP, a hydrogen ion and a D-gluconate 6-phosphate. This compound can either join the Entner-Doudoroff pathway or be metabolized by a NADP dependent 6-phosphogluconate dehydrogenase resulting in a NADPH, a carbon dioxide and a D-ribulose 5-phosphate. The Entner-doudoroff pathway is dehydrated by a phosphogluconate dehydratase resulting in a water molecule and a 2-dehydro-3-deoxy-D-gluconate 6-phosphate. This compound then interacts with a 2-keto-3-deoxygluconate 6-phosphate aldolase resulting in a D-glyceraldehyde 3-phosphate and a pyruvic acid. The d-glyceraldehyde 3-phosphate is incorporated into a glycolysis while the pyruvic acid is decarboxylated into acetyl CoA

Histidine biosynthesis starts with a product of PRPP biosynthesis pathway, phosphoribosyl pyrophosphate which interacts with a hydrogen ion through an ATP phosphoribosyltransferase resulting in an pyrophosphate and a phosphoribosyl-ATP. The phosphoribosyl-ATP interacts with water through a phosphoribosyl-AMP cyclohydrolase / phosphoribosyl-ATP pyrophosphatase resulting in the release of pyrophosphate, hydrogen ion and a phosphoribosyl-AMP. The same enzyme proceeds to interact with phosphoribosyl-AMP and water resulting in a 1-(5'-Phosphoribosyl)-5-amino-4-imidazolecarboxamide. The product is then isomerized by a N-(5'-phospho-L-ribosyl-formimino)-5-amino-1-(5'-phosphoribosyl)-4-imidazolecarboxamide isomerase resulting in a PhosphoribosylformiminoAICAR-phosphate, which reacts with L-glutamine through an imidazole glycerol phosphate synthase resulting in a L-glutamic acid, hydrogen ion, 5-aminoimidazole-4-carboxamide and a D-erythro-imidazole-glycerol-phosphate. D-erythro-imidazole-glycerol-phosphate reacts with a imidazoleglycerol-phosphate dehydratase / histidinol-phosphatase, dehydrating the compound and resulting in a imidazole acetol-phosphate. Next, imidazole acetol-phosphate reacts with L-glutamic acid through a histidinol-phosphate aminotransferase, releasing oxoglutaric acid and L-histidinol-phosphate. The latter compound interacts with water and a imidazoleglycerol-phosphate dehydratase / histidinol-phosphatase resulting in L-histidinol and phosphate. L-histidinol interacts with a NAD-driven histidinol dehydrogenase resulting in a Histidinal. Histidinal in turn reacts with water in a NAD driven histidinal dehydrogenase resulting in L-Histidine. L-Histidine then represses ATP phosphoribosyltransferase, regulation its own biosynthesis.